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1.
Food Chem ; 368: 130772, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34399182

RESUMO

Macrolepiota albuminosa (Berk.) Pegler is abundant in active polysaccharides, but little is known about their structures and solution properties. In this study, water-extracted polysaccharides from M. albuminosa (MAWP) were purified into three fractions with structural heterogeneity, which was attributed to the diversity in molecular weight, monosaccharide composition and linkage patterns, further affecting their solution properties. Methylation and NMR analysis revealed MAWP-60p and MAWP-70 were a 3-O-methylated glucomannogalactan and a previously unreported glucomannogalactan, whereas MAWP-80 was elucidated as a branched galactoglucan. Besides, three fractions exhibited random coil conformation in aqueous solution, while MAWP-60p had the highest viscosity due to its highest molecular weight, mean square radius of gyration (Rg) and O-methyl group attached to the backbone. The molecular weight, monosaccharide composition and glycosidic linkages might be the major contributors to the flexibility, molecular size and stereochemistry of mushroom polysaccharide chains.


Assuntos
Agaricales , Polissacarídeos , Carboidratos da Dieta , Peso Molecular , Monossacarídeos , Viscosidade
2.
Methods Mol Biol ; 2303: 297-306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34626388

RESUMO

Glycosaminoglycans (GAGs) are heterogeneous biomacromolecules made by all animal cells with overlapping molecular weight and high negative charge densities, which make thorough separation of different types of GAGs and elimination of all GAG-binding proteins difficult. Even with the constant challenge of quality control, chondroitin sulfate, dermatan sulfate, heparan sulfate, and heparin glycosaminoglycans (GAGs) have been used as nutraceuticals and modern drugs for many years worldwide. Testing galactosamine in heparin has been added to the USP monograph after contaminated heparin event, but the general monosaccharide composition analysis has not been developed for GAG quality control purposes. Using a PCR-facilitated hydrolysis assay, the hydrolyzed GAG saccharides were labeled with 1-phenyl-3-methyl-5-pyrazolone (PMP) and quantified by high performance liquid chromatography (HPLC) coupled with mass spectrometry (MS). Glucosamine was found in both chondroitin sulfate and dermatan sulfate whereas galactosamine was observed in both heparan sulfate and heparin, indicating the cross contamination among different types of GAGs. Moreover, fucose was detected in chondroitin sulfate, dermatan sulfate, and heparan sulfate, and both fucose and mannose were detected in chondroitin sulfate, suggesting the co-presence of other types of glycans or novel fucosylated GAG structures. Furthermore, both the amount and structure of acid-resistant disaccharides provide distinguishable features for each type of GAGs at the same hydrolysis condition. Thus, monosaccharide analysis provides a practical and quantitative way for GAG quality control.


Assuntos
Glicosaminoglicanos/química , Animais , Sulfatos de Condroitina , Dermatan Sulfato , Fucose , Galactosamina , Heparina , Heparitina Sulfato , Monossacarídeos , Controle de Qualidade
3.
Rocz Panstw Zakl Hig ; 72(4): 419-426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34928118

RESUMO

Background: Irritable bowel syndrome (IBS) is the most common gastrointestinal disorder that is driven by the gutbrain axis and affects 1-20% of the population. Most patients note that various foods elicit abdominal symptoms, and they eliminate these products from their diets. A diet that is low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) is currently one of the mainstays in IBS treatment. Objective: The aim of this study was to assess the knowledge of IBS patients about the disease, treatment and the principles of the low-FODMAP diet that can alleviate gastrointestinal symptoms. Material and methods: The participants were adults diagnosed with IBS, the inclusion criteria were: absence of comorbidities requiring an elimination diet, age over 18 years, and consent to participate in the study. The respondents filled out an anonymous questionnaire containing questions about the IBS diagnosis, disease history and treatment, as well as 45 questions assessing the participants' knowledge about the low-FODMAP diet. Results: In 28% of the cases, IBS was diagnosed by a general practitioner; in nearly 40% of the cases - by a gastroenterology specialist; in 10% of the cases - by a dietitian, whereas the remaining respondents had arrived at the diagnosis independently or with the help of support groups for IBS patients. After diagnosis, only every fourth respondent sought treatment in a gastroenterology clinic. In the studied population, 237 of the respondents had followed to the low-FODMAP diet, and the differentiating factors were sex (p=0.002), place of residence (city with a population higher than 100,000 vs. rural area; p=0.0001) and education (university vs. vocational school p=0.0043). Respondents who had been recently diagnosed with IBS (less than 12 months vs. more than 12 months before the study) were more likely to follow the FODMAP diet. Conclusions: The surveyed population was characterized by high levels of knowledge about the low-FODMAP diet, but many respondents did not strictly comply with dietary guidelines, in particular the duration of each dietary phase. Age was significantly correlated with the respondents' knowledge, and the participants' familiarity with low-FODMAP guidelines decreased with age. Nutritional consultations did not significantly improve the respondents' knowledge about the low-FODMAP diet.


Assuntos
Síndrome do Intestino Irritável , Adolescente , Dieta , Dissacarídeos , Humanos , Monossacarídeos , Política Nutricional
4.
Nutrients ; 13(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34960065

RESUMO

(1) Background: Specific foods, and more particularly, fermentable oligo-, di-, and mono-saccharides and polyols (FODMAPs) are often considered as triggers of digestive symptoms in Irritable Bowel Syndrome (IBS). Our aim was to study FODMAP consumption in controls and IBS participants in a large French population-based cohort; (2) Methods: Participants from the NutriNet-Santé cohort study completed the Rome IV and IBS-SSS questionnaire in a cross sectional study. Among them, 27,949 eligible participants had previously completed three 24-h recalls as well as anthropometrics, socio-demographical and lifestyle data. Total FODMAP intake (in g/day) was computed using a specific composition table. The association between FODMAPs and IBS was estimated through multivariable logistic regression models; (3) Results: Included participants were mainly women (75.4%) and the mean age was 43.4 ± 14.1 years. FODMAPs accounted for a mean daily intake of 19.4 ± 9.5 g/day. Overall 1295 participants (4.6%) were identified with an IBS. After adjusting for confounding factors, IBS participants had lower intakes in FODMAPs than non-IBS ones (aOR: 0.88, 95% CI: 0.82-0.95, p-value: 0.001). IBS severity was associated with more frequent low FODMAP intakes (<9 g/day); (4) Conclusions: Participants tended to consume 19 g of FODMAPs per day, but slightly less for IBS participants than for controls. In IBS participants, higher severity was associated with lower intakes.


Assuntos
Dieta/efeitos adversos , Dissacarídeos/efeitos adversos , Síndrome do Intestino Irritável/induzido quimicamente , Monossacarídeos/efeitos adversos , Oligossacarídeos/efeitos adversos , Adulto , Estudos de Coortes , Feminino , Fermentação , Análise de Alimentos , França , Humanos , Masculino , Pessoa de Meia-Idade , Polímeros
5.
Acta Gastroenterol Belg ; 84(4): 593-600, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34965041

RESUMO

Background and aims: Efficiency of a low FODMAPs diet (LFD) to relieve symptoms in patients with irritable bowel syndrome (IBS) has been proved in several studies. Our study aimed to evaluate the management of IBS-patients when explanations about LFD are given by the physician without dietician intervention. Patients and methods: Patients with IBS were evaluated prospectively after explanations about the LFD were given with the help of a leaflet. A first questionnaire evaluating trigger foods and diet acceptability was submitted to the patient after the consultation. Six weeks later, a second questionnaire evaluated patient's understanding and adherence to the diet, the evolution of symptoms, and the need for a specific dietetic support. Results: Thirty-five patients were included (69% female; mean age 45±15). Seventy-four percent of the patients thought that their symptoms were related to food ingestion, and 97% were ready to go on a diet to improve their symptoms. During the second visit, 91% of the patients reported understanding correctly the explanations, 52% followed LFD regularly, 28% sometimes and 20% did not follow LFD at all or barely. Multiple non-adherence factors were reported. All symptoms, except constipation, decreased significantly six weeks after starting LFD. Finally, 77% of the patients reported satisfaction with care and 69% were willing to be supported by a dietician. Conclusions: Most IBS patients understood explanations given by GI physicians, but low compliance to the diet and a wish for dietician support was highlighted, suggesting that a dietician intervention should be scheduled when LFD is implemented.


Assuntos
Síndrome do Intestino Irritável , Nutricionistas , Adulto , Dieta , Dieta com Restrição de Carboidratos , Dissacarídeos , Estudos de Viabilidade , Feminino , Fermentação , Humanos , Masculino , Pessoa de Meia-Idade , Monossacarídeos , Oligossacarídeos , Estudos Prospectivos , Qualidade de Vida
6.
J Equine Vet Sci ; 105: 103731, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34607684

RESUMO

For a period of 20 days, 12 horses either received a prebiotic supplementation with fructooligosaccharides and inulin via Jerusalem artichoke meal (JAM) or corncob meal without grains (CMG) as placebo. The horses were euthanized 1 hour postprandial, gastric digesta was sampled from pars nonglandularis (PNG) and pars glandularis (PG), and concentrations of starch, mono- and disaccharides, fructans, d- and l-lactic acid, and short chain fatty acids were analyzed. Concentrations of starch and simple sugars were widely the same in JAM supplemented and not supplemented meals. However, fructans were less than half as much without supplementation as with supplementation of JAM. Glucose, fructose, sucrose, and fructans disappeared to a larger extent with prebiotic supplementation than without (106.6% vs. 86.7% glucose, 73.1% vs. 66.8% fructose, 91.5% vs. 14.7% sucrose, and 68.3% vs. 35.4% fructans remained in PNG; 81.9% vs. 38.3% glucose, 52.2% vs. 53.4% fructose, 47.1% vs. 0% sucrose, and 48.5% vs. 31.7% fructans remained in PG with CMG vs. JAM feeding). Disappearance of simple sugars and fructans was primarily associated with appearance of n-butyric acid (r = -0.21 - r = -0.33).


Assuntos
Helianthus , Inulina , Animais , Dissacarídeos , Frutanos , Cavalos , Monossacarídeos , Oligossacarídeos , Prebióticos , Estômago
7.
J Chem Inf Model ; 61(10): 4940-4948, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34595926

RESUMO

This article describes features, usage, and application of an CSDB/SNFG Structure Editor, a new online tool for quick and intuitive input of carbohydrate and derivative structures using Symbol Nomenclature for Glycans (SNFG). The Editor is built on a platform of the Carbohydrate Structure Database (CSDB) and relies on its online services via the dedicated web-API. The Editor allows building of oligo- and polymeric glycan structures and supports most features of natural glycans, such as underdetermined structures, alternative branches, repeating subunits, SMILES specification of atypical monomers, and others. The vocabulary of building blocks contains 600+ monomeric residues, including 327 monosaccharides. Support for SMILES allows input and visualization of chemical structures of virtually unlimited complexity. On the other hand, the interface follows the recognized GlycanBuilder style easy to novice users. The export feature includes support for CSDB Linear, GlycoCT, WURCS, SweetDB, and Glycam notations, SMILES codes, MOL/PDB atomic coordinate formats, raster and vector SNFG images, and on-the-fly visualization as 2D structural formulas and 3D molecular models. Integration of the Editor into any web-based glycoinformatics project is straightforward and simple, similarly to any other modern JavaScript application.


Assuntos
Carboidratos , Polissacarídeos , Bases de Dados Factuais , Monossacarídeos
8.
Molecules ; 26(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34641464

RESUMO

The combination of saccharides in the composition of a cryopreservation medium may represent a promising method for the preservation of the reproductive cells of male birds. In the current study, cryoprotective media with a combined composition of mono- and di-saccharides were developed. The degree of penetration of reducing saccharide molecules (maltose-Mal20 medium) and non-reducing disaccharide molecules (trehalose-Treh20 medium) from the cryoprotective medium into the cytosol of rooster spermatozoa was studied. LCM control media without disaccharides were used as the control. The number of maltose molecules penetrating from the outside into the cytosol of the spermatozoon was 1.06 × 104, and the number of trehalose molecules was 3.98 × 104. Using a combination of maltose and fructose, the progressive motility of frozen/thawed semen and the fertility rates of eggs were significantly higher ((p < 0.05) 40.2% and 68.5%, respectively) than when using a combination of trehalose and fructose in a cryoprotective diluent (33.4% and 62.4%, respectively). A higher rate of chromatin integrity at the level of 92.4% was obtained when using Treh20 versus 74.5% Mal20 (p < 0.05). Maltose positively affected the preservation of frozen/thawed sperm in the genital tract of hens. On the seventh day from the last insemination when using Mal20, the fertilization of eggs was 42.6% and only 27.3% when using Treh20. Despite the same molecular weight, maltose and trehalose have different physicochemical and biological properties that determine their function and effectiveness as components of cryoprotective media.


Assuntos
Criopreservação/veterinária , Crioprotetores/administração & dosagem , Dissacarídeos/administração & dosagem , Monossacarídeos/administração & dosagem , Preservação do Sêmen/veterinária , Motilidade Espermática , Animais , Galinhas , Criopreservação/métodos , Masculino , Preservação do Sêmen/métodos
9.
Food Res Int ; 148: 110588, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507733

RESUMO

Monosaccharides of Keemun black tea were quantitatively determined by high performance liquid chromatography coupled with 3-methyl-1-phenyl-2-pyrazolin-5-one (PMP) pre-column derivatization. The methodology of developed analytical method was established with good linearity, recovery, repeatability and precision. The quantitative results showed that D-mannose, D-glucuronic acid, D-glucose, D-galactose and L-arabinose were detected in Keemun black tea samples. D-glucose was the predominant monosaccharide in black tea, and its concentration was continuously increased from fresh tea leaves to fermentation, but after drying its concentration was significantly decreased. Meanwhile, theaflavins' concentrations were obviously decreased after drying. When theaflavins were heated with D-glucose, the loss of theaflavins was increased. Correspondingly, theaflavins also prevented the caramelization of D-glucose and restored the loss of D-glucose during heating. Through the liquid chromatography/electrospray tandem mass spectrometry some theaflavins glucose adducts were identified.


Assuntos
Biflavonoides , Chá , Biflavonoides/análise , Catequina , Glucose , Monossacarídeos
10.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502058

RESUMO

A lignin fraction (LF) was extracted from the sea balls of Posidonia oceanica (egagropili) and extensively dialyzed and characterized by FT-IR and NMR analyses. LF resulted water soluble and exhibited a brownish-to-black color with the highest absorbance in the range of 250-400 nm, attributed to the chromophore functional groups present in the phenylpropane-based polymer. LF high-performance size exclusion chromatography analysis showed a highly represented (98.77%) species of 34.75 kDa molecular weight with a polydispersity index of 1.10 and an intrinsic viscosity of 0.15. Quantitative analysis of carbohydrates indicated that they represented 28.3% of the dry weight of the untreated egagropili fibers and 72.5% of that of LF. In particular, eight different monosaccharides were detected (fucose, arabinose, rhamnose, galactose, glucose, xylose, glucosamine and glucuronic acid), glucuronic acid (46.6%) and rhamnose (29.6%) being the most present monosaccharides in the LF. Almost all the phenol content of LF (113.85 ± 5.87 mg gallic acid eq/g of extract) was water soluble, whereas around 22% of it consisted of flavonoids and only 10% of the flavonoids consisted of anthocyanins. Therefore, LF isolated from egagropili lignocellulosic material could be defined as a water-soluble lignin/carbohydrate complex (LCC) formed by a phenol polymeric chain covalently bound to hemicellulose fragments. LCC exhibited a remarkable antioxidant activity that remained quite stable during 6 months and could be easily incorporated into a protein-based film and released from the latter overtime. These findings suggest egagropili LCC as a suitable candidate as an antioxidant additive for the reinforcement of packaging of foods with high susceptibility to be deteriorated in aerobic conditions.


Assuntos
Alismatales/química , Antioxidantes/química , Lignina/química , Monossacarídeos/química , Extratos Vegetais/química , Ácido Gálico/química , Glucosamina/química , Fenóis/química , Proteínas/química , Viscosidade
11.
Chemistry ; 27(55): 13719-13724, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34486179

RESUMO

The sialic acid N-acetylneuraminic acid (Neu5Ac) and its derivatives are involved in many biological processes including cell-cell recognition and infection by influenza. Molecules that can recognize Neu5Ac might thus be exploited to intervene in or monitor such events. A key obstacle in this development is the sparse availability of easily prepared molecules that bind to this carbohydrate in its natural solvent; water. Here, we report that the carbohydrate binding pocket of an organic soluble [Pd2 L4 ]4+ cage could be equipped with guanidinium-terminating dendrons to give the water soluble [Pd2 L4 ][NO3 ]16 cage 7. It was shown by means of NMR spectroscopy that 7 binds selectively to anionic monosaccharides and strongest to Neu5Ac with Ka =24 M-1 . The cage had low to no affinity for the thirteen neutral saccharides studied. Aided by molecular modeling, the selectivity for anionic carbohydrates such as Neu5Ac could be rationalized by the presence of charge assisted hydrogen bonds and/or the presence of a salt bridge with a guanidinium solubilizing arm of 7. Establishing that a simple coordination cage such as 7 can already selectively bind to Neu5Ac in water paves the way to improve the stability, affinity and/or selectivity properties of M2 L4 cages for carbohydrates and other small molecules.


Assuntos
Monossacarídeos , Água , Guanidina , Ligação de Hidrogênio , Solventes
12.
J Org Chem ; 86(18): 12973-12987, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34478619

RESUMO

Reductive openings of cyclic acetals are widely used in modern synthetic organic chemistry for the regioselective introduction of protecting groups. A systematic study was performed on the applicability and efficacy of various hydride donor and protic or Lewis acid reagent combinations in the reductive ring opening of glucosidic 4,6-halobenzylidene acetals bearing an ortho-, meta-, and para-chloro- or -bromo substituent on the benzene ring. Most of the reagent combinations tested cleaved the 4,6-O-halobenzylidene acetal rings at O4 or O6 efficiently and with the expected regioselectivity. The LiAlH4-AlCl3 and the BH3·THF-TMSOTf combinations produced the 4-O-halobenzyl ether/6-OH products with complete regioselectivity and high yields. The use of Me3N·BH3-AlCl3 reagent system in toluene was also effective in cleaving the acetal ring at O6 but was accompanied by Al-chelation-assisted debenzylation side reactions. The NaCNBH3-HCl and the Et3SiH-BF3·Et2O combinations were highly effective in yielding the 6-halobenzyl ether/4-OH derivatives. Et3SiH, in combination with TfOH, produced the 6-O-ether/4-OH products in rapid reactions but also triggered silylation and reductive halobenzylation as secondary transformations. Reductive opening of the 1,3-dioxane ring of pyranosidic 4,6-O-halobenzylidene acetals by the proper reagent combination was found to be an efficient method for the regioselective introduction of versatile halobenzyl protecting groups onto the pyranose ring.


Assuntos
Acetais , Compostos de Benzilideno , Indicadores e Reagentes , Ácidos de Lewis , Monossacarídeos
13.
Int J Biol Macromol ; 189: 279-291, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34389387

RESUMO

Proteoglycosylation is the addition of monosaccharides or glycans to the protein peptide chain. This is a common post-translational modification of proteins with a variety of biological functions. At present, more than half of all biopharmaceuticals in clinic are modified by glycosylation. Most glycoproteins are potential drug targets and biomarkers for disease diagnosis. Therefore, in-depth study of glycan structure of glycoproteins will ultimately improve the sensitivity and specificity of glycoproteins for clinical disease detection. With the deepening of research, the function and application value of glycans and glycosylation has gradually emerged. This review systematically introduces the latest research progress of glycans and glycosylation. It encompasses six cancers, four viruses, and their latest discoveries in Alzheimer's disease, allergic diseases, congenital diseases, gastrointestinal diseases, inflammation, and aging.


Assuntos
Glicoproteínas/química , Polissacarídeos/química , Proteoglicanas/metabolismo , Glicoproteínas/metabolismo , Glicosilação , Humanos , Monossacarídeos , Polissacarídeos/metabolismo , Processamento de Proteína Pós-Traducional , Proteoglicanas/química
14.
J Enzyme Inhib Med Chem ; 36(1): 1798-1809, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34348556

RESUMO

Identifying isoform-specific inhibitors for closely related kinase family members remains a substantial challenge. The necessity for achieving this specificity is exemplified by the RSK family, downstream effectors of ERK1/2, which have divergent physiological effects. The natural product, SL0101, a flavonoid glycoside, binds specifically to RSK1/2 through a binding pocket generated by an extensive conformational rearrangement within the RSK N-terminal kinase domain (NTKD). In modelling experiments a single amino acid that is divergent in RSK3/4 most likely prevents the required conformational rearrangement necessary for SL0101 binding. Kinetic analysis of RSK2 association with SL0101 and its derivatives identified that regions outside of the NTKD contribute to stable inhibitor binding. An analogue with an n-propyl-carbamate at the 4" position on the rhamnose moiety was identified that forms a highly stable inhibitor complex with RSK2 but not with RSK1. These results identify a SL0101 modification that will aid the identification of RSK2 specific inhibitors.


Assuntos
Benzopiranos/síntese química , Monossacarídeos/síntese química , Inibidores de Proteínas Quinases/síntese química , Proteínas Quinases S6 Ribossômicas 90-kDa/antagonistas & inibidores , Sequência de Aminoácidos , Benzopiranos/metabolismo , Carbamatos/química , Humanos , Cinética , Modelos Moleculares , Monossacarídeos/metabolismo , Ligação Proteica , Conformação Proteica , Inibidores de Proteínas Quinases/metabolismo , Ramnose/química , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Relação Estrutura-Atividade
15.
Nat Commun ; 12(1): 4924, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389709

RESUMO

C-Glycosyl peptides/proteins are metabolically stable mimics of the native glycopeptides/proteins bearing O/N-glycosidic linkages, and are thus of great therapeutical potential. Herein, we disclose a protocol for the syntheses of vinyl C-glycosyl amino acids and peptides, employing a nickel-catalyzed reductive hydroglycosylation reaction of alkyne derivatives of amino acids and peptides with common glycosyl bromides. It accommodates a wide scope of the coupling partners, including complex oligosaccharide and peptide substrates. The resultant vinyl C-glycosyl amino acids and peptides, which bear common O/N-protecting groups, are amenable to further transformations, including elongation of the peptide and saccharide chains.


Assuntos
Alcinos/química , Aminoácidos/química , Glicosídeos/química , Níquel/química , Peptídeos/química , Brometos/química , Sequência de Carboidratos , Catálise , Dissacarídeos/química , Glicopeptídeos/síntese química , Glicopeptídeos/química , Glicosídeos/síntese química , Glicosilação , Modelos Químicos , Estrutura Molecular , Monossacarídeos/química , Oxirredução
16.
Phys Chem Chem Phys ; 23(32): 17656-17662, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34373871

RESUMO

In this manuscript the ability of selenium carbohydrates to undergo chalcogen bonding (ChB) interactions with protein residues has been studied at the RI-MP2/def2-TZVP level of theory. An inspection of the Protein Data Bank (PDB) revealed SeA (A = O, C and S) intermolecular contacts involving Se-pyranose ligands and ASP, TYR, SER and MET residues. Theoretical models were built to analyse the strength and directionality of the interaction together with "Atoms in Molecules" (AIM), Natural Bonding Orbital (NBO) and Non Covalent Interactions plot (NCIplot) analyses, which further assisted in the characterization of the ChBs described herein. We expect that the results from this study will be useful to expand the current knowledge regarding biological ChBs as well as to increase the visibility of the interaction among the carbohydrate chemistry community.


Assuntos
Lectinas/metabolismo , Monossacarídeos/metabolismo , Compostos Organosselênicos/metabolismo , Agaricales/química , Aspergillus oryzae/química , Bases de Dados de Proteínas , Escherichia coli/química , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Ligação de Hidrogênio , Lectinas/química , Modelos Moleculares , Monossacarídeos/química , Compostos Organosselênicos/química , Ligação Proteica , Selênio/química , Eletricidade Estática , Termodinâmica
17.
Nutrients ; 13(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34371973

RESUMO

We conducted a meta-analysis exploring the effect of a low fermentable oligo-, di-, monosaccharides, and polyols diet (LFD) on the overall symptoms, quality of life, and stool habits of irritable bowel syndrome (IBS) patients. The meta-analysis was performed using a random-effects method. The effect size was presented as weighted standardized mean difference (SMD) and 95% confidence interval (CI). Subgroup analyses were conducted to determine the potential effects of covariates on the outcome. Twenty-two papers were included. The LFD group showed a moderate reduction in symptom severity and a slight improvement in quality of life compared to the control group (SMD, -0.53 and 0.24; 95% CI, -0.68, -0.38 and 0.02, 0.47, respectively). IBS symptom improvement was consistent between subgroups stratified according to proportions of female patients, study durations, IBS subtypes, assessment methods, and control interventions. Three studies regarding stool habits change in IBS-D patients showed a significant decrease in stool frequency (mean differences [MD], -5.56/week; 95% CI, -7.40, -3.72) and a significant improvement in stool consistency (MD, -0.86; 95% CI, -1.52, -0.19) in the LFD group compared to the control group. This is the most updated meta-analysis including studies that adopted diverse control interventions such as dietary interventions, supplementation, habitual diets, and lifestyle changes.


Assuntos
Dieta com Restrição de Carboidratos , Fermentação , Síndrome do Intestino Irritável/dietoterapia , Dietoterapia/métodos , Suplementos Nutricionais , Dissacarídeos , Humanos , Síndrome do Intestino Irritável/fisiopatologia , Monossacarídeos , Oligossacarídeos , Polímeros , Comportamento de Redução do Risco , Índice de Gravidade de Doença , Resultado do Tratamento
18.
Nutrients ; 13(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34371976

RESUMO

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (LFD) improves both gastrointestinal (GI) symptoms and the psychological profile of patients with irritable bowel syndrome with diarrhea (IBS-D). The effects of 12 weeks of LFD on GI symptom and psychological profiles in relation to inflammation and the involvement of the intestinal barrier were studied in twenty IBS-D patients. The IBS Severity Scoring System, the Symptom Checklist-90-Revised, the Italian version of the 36-Item Short-Form Health Survey, the IBS-Quality of Life (QoL) questionnaire, and the Psychophysiological questionnaire were administered. The GI barrier function was assessed by sugar absorption test, the serum and fecal zonulin levels, and the serum levels of intestinal fatty-acid binding protein and diamine oxidase. Interleukins (ILs) and lipopolysaccharide (LPS) serum levels were evaluated along with dysbiosis. At the end of LFD, GI symptoms, psychological state (mainly anxiety, somatization, psychoticism, and interpersonal sensitivity), and QoL significantly improved in these patients. Simultaneously, an improvement in small intestinal permeability and intestinal mucosal integrity occurred, while IL-6, Il-10, LPS, and fermentative dysbiosis significantly decreased. The LFD can modify the immune-inflammatory features and enhance intestinal permeability and mucosal integrity, thus determining a concurrent improvement in the clinical and psychological conditions.


Assuntos
Dieta com Restrição de Carboidratos , Fermentação , Trato Gastrointestinal/fisiopatologia , Intestinos/fisiopatologia , Síndrome do Intestino Irritável/dietoterapia , Síndrome do Intestino Irritável/psicologia , Adulto , Diarreia/fisiopatologia , Dissacarídeos , Feminino , Humanos , Inflamação/fisiopatologia , Absorção Intestinal/fisiologia , Mucosa Intestinal/fisiopatologia , Síndrome do Intestino Irritável/fisiopatologia , Masculino , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Monossacarídeos , Oligossacarídeos , Polímeros/administração & dosagem , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e Questionários
19.
Angew Chem Int Ed Engl ; 60(43): 23171-23175, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34463017

RESUMO

An automated continuous flow system capable of producing protected deoxy-sugar donors from commercial material is described. Four 2,6-dideoxy and two 3-amino-2,3,6-trideoxy sugars with orthogonal protecting groups were synthesized in 11-32 % overall yields in 74-131.5 minutes of total reaction time. Several of the reactions were able to be concatenated into a continuous process, avoiding the need for chromatographic purification of intermediates. The modular nature of the experimental setup allowed for reaction streams to be split into different lines for the parallel synthesis of multiple donors. Further, the continuous flow processes were fully automated and described through the design of an open-source Python-controlled automation platform.


Assuntos
Amino Açúcares/síntese química , Desoxiaçúcares/síntese química , Monossacarídeos/síntese química
20.
J Food Biochem ; 45(9): e13871, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34402085

RESUMO

A novel polysaccharide fraction (HEP) from Hericium erinaceus was successively isolated and purified in the present study. We researched its structure and thermal stabilities, and further studied its antioxidant activities in vitro. The results showed that HEP was an acid heteropolysaccharide, with an average molecular weight of approximately 19.7 kDa by high-performance gel permeation chromatography. Ion chromatography indicated that HEP was mainly composed of fucose:galactose:glucose:mannose:gluconic acid (Fuc:Gal:Glu:Man:GlcA) in a molar ratio of 1:2.87:0.09:0.12:0.01. Additionally, Fourier-transformed infrared and NMR spectroscopy further demonstrated that HEP was a pyranose containing α-configuration, mainly consisting of α-1-4-Fuc and α-1-6-Gal as the main chain, with →3,6)-α-D-Man-(1→and→1,6)-Glc was branched, with α-D-GlcpA-(1 as T-terminal. The specific rotation of HEP was +55°; by the differential scanning calorimetry and the thermal stability measurement of thermogravimetric analysis for HEP showed that the pyrolysis process of HEP was mainly divided into two processes, and its melting point was 75.93℃. In vitro anti-oxidation experiments showed that HEP had a certain ability to scavenge DPPH, hydroxyl, superoxide anion, and ABTS radicals. It was found that HEP had a strong ability to scavenge DPPH-free radicals, and the highest scavenging rate could reach 91.72% ± 0.17%, which was basically equivalent to the scavenging ability of Vitamin C (Vc). Therefore, it was revealed that HEP might be used as a natural antioxidant component. PRACTICAL APPLICATIONS: A novel polysaccharide (HEP) had a potent activity possibly due to its monosaccharide composition, sugar residues, and physicochemical properties. This research proved the potential of HEP in anti-oxidation and provided the possibility of developing new natural anti-oxidation products.


Assuntos
Antioxidantes , Hericium , Antioxidantes/farmacologia , Humanos , Peso Molecular , Monossacarídeos , Polissacarídeos/farmacologia
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